i2c: piix4: Fix adapter not be removed in piix4_remove()

Description

In the Linux kernel, the following vulnerability has been resolved: i2c: piix4: Fix adapter not be removed in piix4_remove() In piix4_probe(), the piix4 adapter will be registered in: piix4_probe() piix4_add_adapters_sb800() / piix4_add_adapter() i2c_add_adapter() Based on the probed device type, piix4_add_adapters_sb800() or single piix4_add_adapter() will be called. For the former case, piix4_adapter_count is set as the number of adapters, while for antoher case it is not set and kept default *zero*. When piix4 is removed, piix4_remove() removes the adapters added in piix4_probe(), basing on the piix4_adapter_count value. Because the count is zero for the single adapter case, the adapter won't be removed and makes the sources allocated for adapter leaked, such as the i2c client and device. These sources can still be accessed by i2c or bus and cause problems. An easily reproduced case is that if a new adapter is registered, i2c will get the leaked adapter and try to call smbus_algorithm, which was already freed: Triggered by: rmmod i2c_piix4 && modprobe max31730 BUG: unable to handle page fault for address: ffffffffc053d860 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 3752 Comm: modprobe Tainted: G Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:i2c_default_probe (drivers/i2c/i2c-core-base.c:2259) i2c_core RSP: 0018:ffff888107477710 EFLAGS: 00000246 ... <TASK> i2c_detect (drivers/i2c/i2c-core-base.c:2302) i2c_core __process_new_driver (drivers/i2c/i2c-core-base.c:1336) i2c_core bus_for_each_dev (drivers/base/bus.c:301) i2c_for_each_dev (drivers/i2c/i2c-core-base.c:1823) i2c_core i2c_register_driver (drivers/i2c/i2c-core-base.c:1861) i2c_core do_one_initcall (init/main.c:1296) do_init_module (kernel/module/main.c:2455) ... </TASK> ---[ end trace 0000000000000000 ]--- Fix this problem by correctly set piix4_adapter_count as 1 for the single adapter so it can be normally removed.

Timeline

Scores

EPSS (exploitation in 30 days)

0.21% · top 88% of all CVEs (12 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.

Affected products

• Linux · Linux

  • affected 528d53a1592b0e27c423f7cafc1df85f77fc1163 – < bfd5e62f9a7ee214661cb6f143a3b40ccc63317f
  • affected 528d53a1592b0e27c423f7cafc1df85f77fc1163 – < d78ccdce662e88f41e87e90cf2bee63c1715d2a5
  • affected 528d53a1592b0e27c423f7cafc1df85f77fc1163 – < fe51636fffc8108c7c4da6aa393010e786530ad9
  • affected 528d53a1592b0e27c423f7cafc1df85f77fc1163 – < 569bea74c94d37785682b11bab76f557520477cd

• Linux · Linux

  • affected 5.4
  • unaffected < 5.4
  • unaffected 5.10.154 – ≤ 5.10.*
  • unaffected 5.15.78 – ≤ 5.15.*
  • unaffected 6.0.8 – ≤ 6.0.*
  • unaffected 6.1 – ≤ *

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2025-12869 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2022-49900](https://cveledger.app/badge/CVE-2022-49900.svg)](https://cveledger.app/cve/CVE-2022-49900)

Record last updated 5 Nov 2026, 20:00 UTC.